Researchers have identified the key to a successful dictatorship

It turns out that most long-lasting dictators have learned a simple trick: Change your top ministers often. Zaire's Mobutu Sese Seko ran through hundreds during his 32 years of rule. 

But just how long do you keep them and which do you change? Change them too soon, and the country is a mess. Too late, and they may threaten your power. Now, researchers from the University of British Columbia and George Mason University have helpfully modelled the problem and can offer well-researched answers.

Keep your key ministers for four years. That's enough time for them to get good at the job, but not enough time to create a power base. And the most dangerous are senior ministers, those controlling defense and finance. Of course, getting rid of key leaders just as they gain real experience isn't great for the economy or defense… but a good dictator probably doesn't fret about that. The Economist has more on the study.

(Editor's note: The Global Scan can be delivered straight to your inbox every weekday. Just register and sign up today.)

A US railroad freight company hauling explosive oil is accused of ignoring safety tests

Current and former employees of Burlington Northern Santa Fe (BNSF) Railway say speed and profits have trumped safety for the company. BNSF is the second largest freight railroad in the US and carries the majority of the especially combustible Bakken crude oil from North Dakota and neighboring states.

PRI's Living on Earth and the collaborative reporting project Earthfix tell the story of a BNSF employee who claims he was relieved, and then fired, when he insisted on checking the air brakes on rail cars before moving a train — a standard safety check. A union official, other BNSF workers and even the US Occupational Safety and Health Administration admit there are problems, but the complaints are tied up in court cases. According to a union representative, “The history of railroads in America has been one where things generally don't get corrected until people die.” 

Russians are hearing that the Malaysia Airlines tragedy was a Western plot

If you have heard that flight MH17 was most likely shot down by pro-Russian Ukrainian separatists, you probably aren’t Russian. Unlike in the rest of the world, much of the Russian media is reporting that Ukraine or the US downed the Malaysia Airlines flight to harm Russia’s reputation.

The New Republic describes some of the conspiracy theories being peddled. One is that Ukraine's military shot down the flight after it mistook the plane for Russian President Vladimir Putin's plane. But the strangest of all is this: The plane was not flight MH17, but actually flight MH370 — the Malaysia Airlines flight that disappeared months ago — now full of corpses and deliberately blown apart over Ukraine to make Russia look bad.

Doctors hope to put people into 'suspended animation' to treat severe injuries

Accidents kill more young people in the US than all diseases combined, in spite of medical advances. One reason is that doctors have very little time to try to repair people in surgery. If blood flow is lost, the brain dies within 3-4 minutes without oxygen.

But researcher Hasan Alam of the University of Michigan Health System and his colleagues think they can change that — by pumping chilled saltwater into the veins of people who have lost much of their blood. That slows the metabolism to the point where cells don't need oxygen for perhaps an hour or two. PRI's Science Friday reports that tests on pigs have worked well, and the researchers are now preparing for human trials.

Iran hopes to bolster its economy and population — by banning vasectomies

Like conservative religious movements the world over, the government of Iran finds sex a difficult topic. But recently, even the Supreme Leader has realized that sex is crucial to the health of the nation. In May, Ayatollah Ali Khamenei published a decree aimed at spurring population growth. Now Iran's Parliament has done him one better. 

Al-Monitor reports that the parliament recently banned vasectomies, imposing "prison sentences of two to five years for anyone engaging in sterilization or other types of reducing fertility." Ironically, the country instituted birth control programs in the late 1980s to combat one of the highest population growth rates in the world. Apparently, that program worked a little too well.

What we're seeing on social

Award-winning Al Jazeera war correspondent breaks down on air while reporting Sunday's Shujaya massacre http://t.co/ioTOAWPrJZ

— Rania Khalek (@RaniaKhalek) July 21, 2014

Weather around the world

Remember the polar vortex that put the northeastern and midwestern US in a deep freeze this past winter? Well, things haven't quite returned to normal for those regions this summer. Today, Chicago had only its third day above 90 degrees Fahrenheit (32 degrees Celsius) for the summer. And cool weather is returning tomorrow, according to forecasters. The Chicago Tribune reports that, so far, July has been 5 degrees Fahrenheit cooler than average for the month, and Chicago is far from the average of 14 days above 90 degrees that it has seen over the last few decades.

It turns out that most long-lasting dictators have learned a simple trick: Change your top ministers often. Zaire's Mobutu Sese Seko ran through hundreds during his 32 years of rule. 

But just how long do you keep them and which do you change? Change them too soon, and the country is a mess. Too late, and they may threaten your power. Now, researchers from the University of British Columbia and George Mason University have helpfully modelled the problem and can offer well-researched answers.

Keep your key ministers for four years. That's enough time for them to get good at the job, but not enough time to create a power base. And the most dangerous are senior ministers, those controlling defense and finance. Of course, getting rid of key leaders just as they gain real experience isn't great for the economy or defense… but a good dictator probably doesn't fret about that. The Economist has more on the study.

(Editor's note: The Global Scan can be delivered straight to your inbox every weekday. Just register and sign up today.)

A US railroad freight company hauling explosive oil is accused of ignoring safety tests

Current and former employees of Burlington Northern Santa Fe (BNSF) Railway say speed and profits have trumped safety for the company. BNSF is the second largest freight railroad in the US and carries the majority of the especially combustible Bakken crude oil from North Dakota and neighboring states.

PRI's Living on Earth and the collaborative reporting project Earthfix tell the story of a BNSF employee who claims he was relieved, and then fired, when he insisted on checking the air brakes on rail cars before moving a train — a standard safety check. A union official, other BNSF workers and even the US Occupational Safety and Health Administration admit there are problems, but the complaints are tied up in court cases. According to a union representative, “The history of railroads in America has been one where things generally don't get corrected until people die.” 

Russians are hearing that the Malaysia Airlines tragedy was a Western plot

If you have heard that flight MH17 was most likely shot down by pro-Russian Ukrainian separatists, you probably aren’t Russian. Unlike in the rest of the world, much of the Russian media is reporting that Ukraine or the US downed the Malaysia Airlines flight to harm Russia’s reputation.

The New Republic describes some of the conspiracy theories being peddled. One is that Ukraine's military shot down the flight after it mistook the plane for Russian President Vladimir Putin's plane. But the strangest of all is this: The plane was not flight MH17, but actually flight MH370 — the Malaysia Airlines flight that disappeared months ago — now full of corpses and deliberately blown apart over Ukraine to make Russia look bad.

Doctors hope to put people into 'suspended animation' to treat severe injuries

Accidents kill more young people in the US than all diseases combined, in spite of medical advances. One reason is that doctors have very little time to try to repair people in surgery. If blood flow is lost, the brain dies within 3-4 minutes without oxygen.

But researcher Hasan Alam of the University of Michigan Health System and his colleagues think they can change that — by pumping chilled saltwater into the veins of people who have lost much of their blood. That slows the metabolism to the point where cells don't need oxygen for perhaps an hour or two. PRI's Science Friday reports that tests on pigs have worked well, and the researchers are now preparing for human trials.

Iran hopes to bolster its economy and population — by banning vasectomies

Like conservative religious movements the world over, the government of Iran finds sex a difficult topic. But recently, even the Supreme Leader has realized that sex is crucial to the health of the nation. In May, Ayatollah Ali Khamenei published a decree aimed at spurring population growth. Now Iran's Parliament has done him one better. 

Al-Monitor reports that the parliament recently banned vasectomies, imposing "prison sentences of two to five years for anyone engaging in sterilization or other types of reducing fertility." Ironically, the country instituted birth control programs in the late 1980s to combat one of the highest population growth rates in the world. Apparently, that program worked a little too well.

What we're seeing on social

Award-winning Al Jazeera war correspondent breaks down on air while reporting Sunday's Shujaya massacre http://t.co/ioTOAWPrJZ

— Rania Khalek (@RaniaKhalek) July 21, 2014

Weather around the world

Remember the polar vortex that put the northeastern and midwestern US in a deep freeze this past winter? Well, things haven't quite returned to normal for those regions this summer. Today, Chicago had only its third day above 90 degrees Fahrenheit (32 degrees Celsius) for the summer. And cool weather is returning tomorrow, according to forecasters. The Chicago Tribune reports that, so far, July has been 5 degrees Fahrenheit cooler than average for the month, and Chicago is far from the average of 14 days above 90 degrees that it has seen over the last few decades.